1. Field of the Invention
The invention relates in general to body protection devices and in particular to a new and useful heat and gas protection suit including an inner suit containing tubular flow channels to receive a liquid cooling agent, and a cooling device, consisting of a heat eschanger with the coolant, and also including a cooling agent circulating pump driven by coolant vapor, and a respirator.
2. Description of the Prior Art
The human body generates heat continuously by metabolism. Normally this heat is transferred to the environment by radiation, conduction, convection and evaporation. The necessary equilibrium, at which the body temperature does not rise beyond the physiological limits, can be attained only if the ambient can absorb the heat as quickly as it is generated. Direct transfer of the heat from the body becomes impossible, however, if the surrounding temperature becomes greater than the permissible upper limit of the human body temperature.
A gas-heat protection suit is known in whose heat-insulating envelope an inner suit with tubular flow channels for the circulation of a liquid cooling agent is disposed. The respective cooling apparatus is accommodated in a backpack and comprises a vessel containing liquid coolant. By structural measures it is taken from the vessel and used via pressure regulating devices to drive the delivery pump for the cooling agent. The cooling agent flows from the pump through a heat exchanger disposed in the coolant vessel to the flow channels in the inner suit and thence back to the delivery pump. Excess coolant gas escapes into the atmosphere. In addition, the backpack contains a closed-cycle respirator. It is supplied with oxygen from a pressure gas bottle. The exhaled carbon dioxide is retained in an absorber. An inhalation air cooler is provided, which is connected to the cooling agent cycle.
Liquid coolant, e.g. ammonia, is dangerous to handle. Discharging NH.sub.3 (ammonia) into the atmosphere in gaseous form is hazardous. Only gaseous coolant should be able to leave the coolant vessel. To be able to dispense always only from the gas phase, a complicated and trouble-prone position compensation is necessary. The protective suit can be used only complete with the respirator, a weight-saving adaptation in the form of a filter device or purely as heat protection does not exist. The oxygen supply from a pressure gas bottle and the additional regeneration cartridge involve a high weight. The circulation of the cooling agent starts with delay after intense evaporation of the coolant has set in. (DT-OS 24 19 524).
Known further is a double-walled protective suit provided with a cooling liquid system. The cooling system of the suit is connected with an outer cooling liquid cycle, in which a heat exchanger cooled by evaporating water provides for the heat transfer from the cooling liquid, and a pump provides for the circulation thereof. In this cycle two additional heat exchangers are arranged, in which respiratory gas and additional oxygen are cooled by the cooling liquid. Also, this cycle has a controllable by-pass between the forward and return branches for temperature regulation and a compensation element for maintaining its internal pressure. The interior of the suit is part of a closed respiratory cycle. In it, the circulation of the respiratory gas occurs by a blower. The exhaled gas coming out of the suit is passed over a carbon dioxide absorber, cooled in a heat exchanger, and sent into the suit again after enrichment with oxygen. The additional oxygen is released from chlorate candles and cooled in a heat exchanger to service temperature. The pump for the cooling liquid and the blower for the respiratory gas are combined in one unit through a magnetic drive and a magnetic coupling and are driven by a common electric motor from a battery. The use of an electric motor and of the heavy battery required for it is disadvantageous. Possible adaptation according to ambient conditions is not provided. A heavy and complicated respirator is used with the device. (U.S. Pat. Ser. No. 3,500,827).